Seismic isolation may be utilized to control or reduce the response of a component or structure to vertical and horizontal ground-input motions or accelerations. Seismic isolation may accomplish this by decoupling the motion of the component/structure from the driving motion of the substructure. In some instances, hardware (e.g., springs) may be positioned between the substructure and superstructure. Use of such hardware may minimize the dynamic response of the structure by increasing the fundamental period of vibration for the component or structure, resulting in lower in-structure accelerations and forces. To further reduce spectral response amplitudes (e.g., deflections, forces, etc.), other mechanisms may be employed that effectively reduce the peak amplitude to manageable levels.
Piping and other connections may be provided between a nuclear reactor and a secondary cooling system or other systems in the power generation facility. In the event of an earthquake or other seismic activity, significant forces or vibration may be transferred to, or by, the connections, which can place great stress on the connections. Forces resulting from thermal expansion also place stress on the connections. Maintaining integrity of these connections helps discourage the inadvertent release of radioactive or other materials from the various systems, and reduces maintenance or damage that might otherwise occur if one or more of the connections fail.
During a seismic event, dynamic and/or seismic forces may be transmitted from the ground, support surface, or surrounding reactor building to a reactor module. The seismic forces which are transferred to the reactor module may experience a cumulative increase and/or amplification in amplitude and/or frequency depending on the number and/or length of intervening structures and/or systems that the seismic forces travel in reaching the reactor module. If the seismic forces become large enough, the reactor core and/or fuel elements may be damaged.
The present invention addresses these and other problems.